U.S. patent application number 13/083833 was filed with the patent office on 2011-10-27 for polishing solution distribution apparatus and polishing apparatus having the same.
This patent application is currently assigned to SUMCO CORPORATION. Invention is credited to Tomohiro HASHII, Yuichi KAKIZONO, Yoshiaki KUROSAWA.
Application Number | 20110263183 13/083833 |
Document ID | / |
Family ID | 44816195 |
Filed Date | 2011-10-27 |
United States Patent
Application |
20110263183 |
Kind Code |
A1 |
KUROSAWA; Yoshiaki ; et
al. |
October 27, 2011 |
POLISHING SOLUTION DISTRIBUTION APPARATUS AND POLISHING APPARATUS
HAVING THE SAME
Abstract
The present invention provides a polishing solution distribution
apparatus capable of reducing distribution deviation of polishing
solution even when leveling for installation is insufficient or
inclination of an installation location varies and a polishing
apparatus having the same. The polishing solution distribution
apparatus includes a cone-shaped branch body in which a solution
pan to store supplied polishing solution is formed and in which
plural flow passages radially connected to a side face of the
solution pan respectively and having a delivery port to supply
polishing solution to a position lower than the connected position
are formed, a support portion to support the branch body, and a
universal joint mechanism to support the branch body via the
support portion at a position being higher than the gravity center
of the branch body.
Inventors: |
KUROSAWA; Yoshiaki; (Tokyo,
JP) ; HASHII; Tomohiro; (Tokyo, JP) ;
KAKIZONO; Yuichi; (Tokyo, JP) |
Assignee: |
SUMCO CORPORATION
Tokyo
JP
|
Family ID: |
44816195 |
Appl. No.: |
13/083833 |
Filed: |
April 11, 2011 |
Current U.S.
Class: |
451/64 ;
451/446 |
Current CPC
Class: |
B24B 37/08 20130101;
B24B 57/02 20130101 |
Class at
Publication: |
451/64 ;
451/446 |
International
Class: |
B24B 57/00 20060101
B24B057/00; B24B 29/02 20060101 B24B029/02 |
Foreign Application Data
Date |
Code |
Application Number |
Apr 26, 2010 |
JP |
2010-100922 |
Claims
1. A polishing solution distribution apparatus comprising: a branch
body in which a solution pan to store supplied polishing solution
is formed and in which plural flow passages radially connected to a
side face of the solution pan respectively and having a delivery
port to supply polishing solution to a position lower than the
connected position are formed; a support portion to support the
branch body; and a universal joint mechanism to support the branch
body via the support portion at a position being higher than the
gravity center of the branch body.
2. The polishing solution distribution apparatus according to claim
1, wherein the plural flow passages have the same inclination in
the flow direction thereof while being connected to the side face
at the same height position.
3. The polishing solution distribution apparatus according to claim
1, wherein a supply portion of polishing solution is arranged above
the solution pan and the supply portion supplies polishing solution
to the solution pan by dropping polishing solution.
4. The polishing solution distribution apparatus according to claim
1, wherein a deadweight to set a height position of the gravity
center of the branch body to be lower than a supported height
position of the branch body by the universal joint mechanism is
attached to the branch body.
5. The polishing solution distribution apparatus according to claim
1, further comprising plural branch piping formed flexibly being
capable of supplying polishing solution to a predetermined position
of a polishing mechanism to perform polishing of a polishing object
as being respectively connected to delivery ports of the plural
flow passages.
6. The polishing solution distribution apparatus according to claim
2, further comprising plural branch piping formed flexibly being
capable of supplying polishing solution to a predetermined position
of a polishing mechanism to perform polishing of a polishing object
as being respectively connected to delivery ports of the plural
flow passages.
7. The polishing solution distribution apparatus according to claim
3, further comprising plural branch piping formed flexibly being
capable of supplying polishing solution to a predetermined position
of a polishing mechanism to perform polishing of a polishing object
as being respectively connected to delivery ports of the plural
flow passages.
8. The polishing solution distribution apparatus according to claim
4, further comprising plural branch piping formed flexibly being
capable of supplying polishing solution to a predetermined position
of a polishing mechanism to perform polishing of a polishing object
as being respectively connected to delivery ports of the plural
flow passages.
9. The polishing solution distribution apparatus according to claim
1, further comprising a funnel being capable of supplying polishing
solution to a predetermined position of a polishing mechanism to
perform polishing of a polishing object as being arranged below the
delivery port having an opening portion directed upward.
10. The polishing solution distribution apparatus according to
claim 2, further comprising a funnel being capable of supplying
polishing solution to a predetermined position of a polishing
mechanism to perform polishing of a polishing object as being
arranged below the delivery port having an opening portion directed
upward.
11. The polishing solution distribution apparatus according to
claim 3, further comprising a funnel being capable of supplying
polishing solution to a predetermined position of a polishing
mechanism to perform polishing of a polishing object as being
arranged below the delivery port having an opening portion directed
upward.
12. The polishing solution distribution apparatus according to
claim 4, further comprising a funnel being capable of supplying
polishing solution to a predetermined position of a polishing
mechanism to perform polishing of a polishing object as being
arranged below the delivery port having an opening portion directed
upward.
13. The polishing solution distribution apparatus according to
claim 5, further comprising a funnel being capable of supplying
polishing solution to a predetermined position of a polishing
mechanism to perform polishing of a polishing object as being
arranged below the branch piping having an opening portion directed
upward.
14. The polishing solution distribution apparatus according to
claim 6, further comprising a funnel being capable of supplying
polishing solution to a predetermined position of a polishing
mechanism to perform polishing of a polishing object as being
arranged below the branch piping having an opening portion directed
upward.
15. The polishing solution distribution apparatus according to
claim 7, further comprising a funnel being capable of supplying
polishing solution to a predetermined position of a polishing
mechanism to perform polishing of a polishing object as being
arranged below the branch piping having an opening portion directed
upward.
16. The polishing solution distribution apparatus according to
claim 8, further comprising a funnel being capable of supplying
polishing solution to a predetermined position of a polishing
mechanism to perform polishing of a polishing object as being
arranged below the branch piping having an opening portion directed
upward.
17. A polishing apparatus comprising the polishing solution
distribution apparatus according to claim 1.
Description
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates to a polishing solution
distribution apparatus to distribute polishing solution for
polishing a workpiece such as a silicon wafer for a semiconductor
and a polishing apparatus having the same.
[0003] 2. Description of the Related Art
[0004] In general, a silicon wafer for a semiconductor is to be
shipped as a product through respective processes of lapping,
etching, polishing, cleaning and inspecting after being cut out
from an ingot by utilizing a diamond saw, a wire saw and the like.
In the polishing process, a carrier which holds a workpiece being a
polishing object is placed between a circular upper platen and a
circular lower platen. Then, spinning and revolving of the carrier
are performed while the upper and lower platens or only the lower
platen is rotated as pouring polishing solution into an area
sandwiched by the upper platen and the lower platen via a polishing
solution supply hole arranged at the upper platen. Accordingly,
upper and lower faces of the workpiece are polished.
[0005] In such a polishing process, it is important to improve
processing accuracy of a workpiece as eliminating deviation of wear
of a platen face by evenly distributing polishing solution to an
area sandwiched by an upper platen and a lower platen.
[0006] Examples of a method to distribute polishing solution in the
related art include a separate valve type having plural branch
piping to adjust flow quantity of respective branch piping with
separate valves, a pump supply type to adjust flow quantity with a
proportioning pump, and a dropping type to distribute polishing
solution dropping to a distributor with plural branch piping. With
the separate valve type, it is difficult to adjust the flow
quantity of each branch piping with adjustment of the separate
valve and the adjustment operation is troublesome since the valves
are arranged at a high location. With the pump supplying type, cost
is increased since the pump is expensive. Accordingly, in general,
the dropping type is adopted as disclosed in Japanese Patent
Application Laid-Open No. 2005-186170, Japanese Utility Model
Application Laid-Open No. 58-191957, Japanese Utility Model
Application Laid-Open No. 47-43116, and the like.
[0007] Japanese Patent Application Laid-Open No. 2005-186170
discloses that distribution deviation of polishing solution is
lessened by placing a sphere body at a funnel-shaped solution
receiving portion to which polishing solution drops and adjusting
flow quantity of the polishing solution with buoyancy force of the
sphere body. Japanese Utility Model Application Laid-Open No.
58-191957 discloses a polishing apparatus in which upper and lower
platens perform rotational motions to supply powder to a polishing
face of the platen through plural tubes from a powder ring with a
concave groove. Japanese Utility Model Application Laid-Open No.
47-43116 discloses a polishing apparatus in which equal quantity of
polishing solution flows to each discharge port arranged at a
distributor as filling sponge body into the distributor so that
polishing solution dropping to the sponge body soaks throughout the
sponge body.
[0008] With the above dropping type in the related art, there has
been a problem that polishing solution cannot be evenly distributed
when leveling for distributor installation is insufficient or
inclination of an installation location varies after installation.
Further, in Japanese Patent Application Laid-Open No. 2005-186170,
there has been a problem that particles contained in polishing
solution are solidified as a result of stagnant flow of polishing
solution depending on weight of the sphere body. In Japanese
Utility-model 47-43116, there also has been a problem that
particles contained in polishing solution stagnate and are hardened
at the sponge body.
SUMMARY OF THE INVENTION
[0009] To address the above issues, the present invention provides
a polishing solution distribution apparatus capable of reducing
deviation of distribution of polishing solution even when leveling
for installation is insufficient or inclination of an installation
location varies and a polishing apparatus having the same.
[0010] Further, the present invention provides a polishing solution
distribution apparatus capable of distributing polishing solution
without solidification of particles contained in polishing solution
due to stagnant flow of polishing solution and a polishing
apparatus having the same.
[0011] A polishing solution distribution apparatus according to the
present invention includes: a branch body in which a solution pan
to store supplied polishing solution is formed and in which plural
flow passages radially connected to a side face of the solution pan
respectively and having a delivery port to supply polishing
solution to a position lower than the connected position are
formed; a support portion to support the branch body; and a
universal joint mechanism to support the branch body via the
support portion at a position being higher than the gravity center
of the branch body.
[0012] According to the present invention, the universal joint
mechanism of the polishing solution distribution apparatus supports
the branch body via the support portion at the position higher than
the gravity center of the branch body. Therefore, even when
leveling for installation of the polishing solution distribution
apparatus is insufficient or inclination thereof varies after
installation, the branch body can be maintained in the leveled
posture against the dropping direction of the polishing solution
and deviation of distribution quantity of the polishing solution to
be distributed to the respective flow passages from the solution
pan can be reduced. Further, since the polishing solution smoothly
flows through the flow passages, the problem of solidification of
particles contained in the polishing solution does not occur.
[0013] In the above configuration, the plural flow passages have
the same inclination in the flow direction thereof while being
connected to the side face at the same height position.
Accordingly, the polishing solution can be evenly branched to the
respective flow passages.
[0014] In the above configuration, a supply portion of polishing
solution is arranged above the solution pan and the supply portion
supplies polishing solution to the solution pan by dropping
polishing solution.
[0015] The above configuration further includes plural branch
piping formed flexibly being capable of supplying polishing
solution to a predetermined position of a polishing mechanism to
perform polishing of a polishing object as being respectively
connected to delivery ports of the plural flow passages.
Accordingly, movement of the branch body is less disturbed by the
branch piping and the branch body can be consistently maintained in
the leveled posture.
[0016] The above configuration further includes a funnel being
capable of supplying polishing solution to a predetermined position
of a polishing mechanism to perform polishing of a polishing object
as being arranged below the delivery port having an opening portion
directed upward. Accordingly, the polishing solution can be
supplied to the polishing mechanism by utilizing the funnel which
does not interfere with movement of the branch piping.
[0017] In the above configuration, a deadweight to set a height
position of the gravity center of the branch body to be lower than
a supported height position of the branch body by the universal
joint mechanism may be attached to the branch body. Accordingly,
the gravity center of the polishing solution distribution apparatus
can be lowered and the leveled posture can be easily
maintained.
[0018] In the above configuration, a polishing apparatus may
include the polishing solution distribution apparatus. Accordingly,
the polishing solution distribution apparatus can distribute
polishing solution evenly to the polishing apparatus, so that
processing accuracy of a workpiece can be improved.
BRIEF DESCRIPTION OF THE DRAWINGS
[0019] FIG. 1 is a front view of a polishing apparatus according to
the first embodiment of the present invention;
[0020] FIG. 2 is an explanatory view of a platen portion of a
polishing mechanism according to the present embodiment;
[0021] FIG. 3 is a schematic longitudinal sectional view of a
polishing solution distribution apparatus and a universal joint
mechanism according to the present embodiment;
[0022] FIG. 4 is a schematic lateral sectional view at line IV-IV
of FIG. 3;
[0023] FIG. 5 is a schematic front view of a polishing apparatus
according to the second embodiment of the present invention;
and
[0024] FIG. 6 is an explanatory view of a modified example of
branch piping.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0025] In the following, embodiments of the present invention will
be described in detail with reference to the drawings. Here, not
limited to the following embodiments, the present invention can be
variously modified without departing from the scope of technical
concept of the invention described in claims.
[0026] FIG. 1 is a front view of a polishing apparatus 40 according
to an embodiment of the present invention. As illustrated in FIG.
1, the polishing apparatus 40 is provided with a polishing
mechanism 3 to polish a workpiece such as a silicon wafer for a
semiconductor and a polishing solution distribution apparatus 10 to
supply polishing solution to the polishing mechanism 3. The
polishing solution distribution apparatus 10 and the polishing
mechanism 3 are connected with branch piping 20. The polishing
solution supplied from a polishing solution supply header pipe to
the polishing solution distribution apparatus 10 is supplied to the
polishing mechanism 3 after passing through the branch piping
20.
[0027] FIG. 2 is an explanatory view of a platen portion of the
polishing mechanism 3. The polishing mechanism 3 is provided with
an inner gear 35 as a sun gear, an outer gear 36 as an internal
gear concentrically arranged at the outside thereof, a carrier 37
which revolves and spins in accordance with rotation of the inner
gear 35 and the outer gear 36, and a platen 30 to vertically
sandwich a workpiece which is held by the carrier 37. The platen 30
includes a circular upper platen 31 having its center at the
position of the inner gear 35 and a circular lower platen 32
arranged below the upper platen 31 as being opposed thereto. The
lower platen 32 is placed on a base 39 (see FIG. 1).
[0028] The upper platen 31 is hung in a pendulum-like manner via a
hanging plate (not illustrated) for hanging of the upper platen 31.
The upper platen 31 applies load to a workpiece held by the carrier
37 with a pressure adjusting mechanism (not illustrated) such as an
air-cylinder.
[0029] The upper platen 31 is provided with plural polishing
solution supply holes 38 piercing in the vertical direction. The
branch piping 20 (see FIG. 1) is connected to each polishing
solution supply hole 38. The polishing solution is supplied, via
the respective polishing solution supply holes 38, to a
donut-shaped area between the inner gear 35 and the outer gear 36
being sandwiched by the upper platen 31 and the lower platen
32.
[0030] FIG. 3 is a schematic longitudinal sectional view of a
polishing solution distribution apparatus 10 and a universal joint
mechanism. FIG. 4 is a schematic lateral sectional view at line
IV-IV of FIG. 3.
[0031] As illustrated in these drawings, the outside of the
polishing solution distribution apparatus 10 is covered with a
cylinder-shaped support portion 11. A top board portion of the
support portion 11 is formed mountain-shaped. A pipe-shaped supply
portion 16 to drop the polishing solution pierces through the apex
portion of the mountain-shape in the vertical direction. The supply
portion 16 is formed of soft material such as thin silicone rubber
to be flexible so as not to disturb operation of the support
portion 11. The polishing solution is supplied to the supply
portion 16 from a supply source of the polishing solution (not
illustrated) via the polishing solution supply header pipe.
[0032] A cone-shaped branch body 12 is arranged at a bottom plate
of the support portion 11. A bottom face of the branch body 12 is
formed to have the approximately same diameter as that of the
support portion 11. A solution pan 122 which temporarily stores the
polishing solution is formed at the apex portion of the cone-shape.
Plural gutter-shaped flow passages 121 are radially formed from the
apex portion of the cone-shape toward a base. An upper end of each
flow passage 121 is connected to a side face of the solution pan
122 at the same height position. A delivery port 123 to discharge
and supply downward the polishing solution passing through the flow
passage 121 is arranged at an intersection position of a lower end
of each flow passage 121 and a side wall of the support portion
11.
[0033] The branch piping 20 is connected to each delivery port 123.
The polishing solution passing through each flow passage 121 is to
be supplied downward to the polishing mechanism 3 side via the
delivery port 123 and the branch piping 20. The branch piping 20 is
formed of soft material such as thin silicone rubber to be flexible
so as not to disturb operation of the branch body 12.
[0034] Here, it is assumed that a three-dimensional orthogonal
coordinate system is defined as Z-axis being the center axis of the
support portion 11 (i.e., the longitudinal direction of the supply
portion 16 arranged at the support portion 11) and as the origin
being a position higher than the gravity center of the branch body
12 in Z-axis. As illustrated in FIG. 4, one end of each first shaft
14, 14 is connected to an outer circumferential face of the support
portion 11 in the direction of X-axis. The other end of each first
shaft 14, 14 is connected to an inner circumferential face of a
ring member 18 of which diameter is size larger than that of the
support portion 11 in the direction of X-axis.
[0035] Each second shaft 15, 15 is connected to an outer
circumferential face of the ring member 18 in the direction of
Y-axis. The second shafts 15, 15 are inserted and supported
respectively to support holes 501, 501 of support poles 50, 50
which are arranged beside both sides of the support portion 11. The
universal joint mechanism is constituted with the first shafts 14,
14, the second shafts 15, 15, the ring member 18, and the support
poles 50, 50. Owing to the universal joint mechanism, the support
portion 11 can flexibly rotate having X-axis and Y-axis as the
rotational axes and the branch body 12 arranged at the bottom plate
of the support portion 11 can take any posture in conjunction with
movement of the support portion 11. Accordingly, the branch body 12
can be maintained on the level against the vertical direction to be
capable of being consistently maintained on the level against the
dropping direction of the polishing solution.
[0036] A deadweight 22 is hung on the lower portion center of the
branch body 12. The deadweight 22 can lower the gravity center of
the branch body 12, thereby enabling the branch body 12 to stably
maintain a leveled posture. Further, since the range of "the
position higher than the gravity center of the branch body 12" is
broadened, restriction for attaching positions of the first shafts
14, 14 and the second shafts 15, 15 can be relaxed. Here, the
attaching position of the deadweight 22 is not limited to the lower
portion center of the branch body 12. For example, the deadweight
22 can be arranged evenly at the circumference of the bottom face
of the branch body 12. In the case that the gravity center of the
polishing solution distribution apparatus 10 is sufficiently low as
a result of forming the branch body 12 with heavy material, for
example, the deadweight 22 may not be arranged.
[0037] The polishing solution supply header pipe to supply the
polishing solution to the supply portion 16 is provided with one
flow meter (not illustrated) and one flow quantity adjusting valve
(not illustrated) respectively. The flow quantity adjusting valve
adjusts the total flow quantity of the polishing solution supplied
to the polishing solution distribution apparatus 10.
[0038] For performing polishing of a workpiece, plural carriers 37
are placed on the lower platen 32 in a state that the upper platen
31 is raised and a workpiece is mounted to each carrier 37. Next,
predetermined load is applied to each workpiece by lowering the
upper platen 31. Subsequently, the polishing solution is dropped
from the polishing solution supply header pipe to the supply
portion 16 of the polishing solution distribution apparatus 10, and
then, the lower platen 32 is rotated at predetermined speed while
supplying the polishing solution to the area sandwiched by the
upper platen 31 and the lower platen 32 via the branch piping 20
connected to the polishing solution distribution apparatus 10.
Accordingly, the plural carriers 37 revolve on the circumference of
the inner gear 35 while spinning, that is, perform planetary
motion.
[0039] Since the branch body 12 is supported by the universal joint
mechanism at the position higher than the gravity center thereof,
the branch body 12 can be consistently maintained in the leveled
posture against the dropping direction of the polishing solution
during the rotation even when leveling for installation of the
polishing solution distribution apparatus 10 is insufficient or
inclination of the installation location varies. Accordingly, the
branch body 12 is capable of evenly distributing, to the flow
passages 121, the polishing solution dropping from the supply
portion 16 to the solution pan 122 and evenly supplying to the area
between the upper platen 31 and the lower platen 32 via the branch
piping 20 and the polishing solution supply holes 38.
[0040] Processing accuracy such as shape and thickness of a
workpiece can be improved by evenly distributing polishing solution
as described above. Further, even in the case of performing
processing treatment such as lapping to cause wear of the platen
30, deviation of wear distribution among respective portions of the
platen 30 can be improved and frequency of maintenance can be
lowered. In the case that deviation of supply quantity of the
polishing solution occurs, it is required to excessively supply the
polishing solution so as to prevent occurrence of operation out of
solution at a portion having less supply quantity. Here, the supply
quantity of the polishing solution can be reduced and manufacturing
cost can be reduced by evenly supplying the polishing solution.
[0041] Further, the total flow quantity can be adjusted only by
arranging one flow meter and one flow quantity adjusting valve at
one position of the polishing solution supply header pipe without
arranging plural valves as a separate valve type in the related
art.
[0042] In addition, with the polishing solution distribution
apparatus 10 according to the present embodiment, flow quantity
adjustment can be performed with a simple structure without causing
stagnation of polishing solution flow by a sponge body, a spherical
body or the like and without utilizing expensive components,
complex piping and the like. Further, even when the polishing
solution distribution apparatus 10 is installed at a high location,
operation for level adjustment becomes unnecessary at the high
location. Here, the shape of the branch body 12 is not limited to a
cone-shape. It is only required that the shape enables the position
of the delivery port 123 to be lower than the position of the
solution pan 122. It is also possible to adopt a pyramid-shape or a
hemisphere-shape like an inversed bowl. Further, the shape of the
flow passages 121 may be spiral. Further, the universal joint
mechanism is not limited to the above as long as being a mechanism
capable of freely varying posture of the polishing solution
distribution apparatus 10 in conjunction with gravity acceleration
and centrifugal force. For example, it is also possible to hang the
polishing solution distribution apparatus 10 from the upper side
with a rope.
[0043] Next, the second embodiment will be described with reference
to FIG. 5. FIG. 5 is a schematic front view of a polishing
apparatus 40a according to the present embodiment. In the polishing
apparatus 40a according to the present embodiment, an upper
polishing solution distribution apparatus 10a is arranged at an
upper stage, plural middle polishing solution distribution
apparatuses 10b are arranged below the upper polishing solution
distribution apparatus 10a, and the polishing mechanism 3 is
arranged below the middle polishing solution distribution apparatus
10b. The upper polishing solution distribution apparatus 10a and
the middle polishing solution distribution apparatus 10b are
configured to be similar to the polishing solution distribution
apparatus 10 illustrated in FIGS. 3 and 4 as described in the first
embodiment. In FIG. 5, the above is illustrated as being
simplified.
[0044] One end of each branch piping 20a is connected to a lower
portion of the upper polishing solution distribution apparatus 10a.
The other end of each branch piping 20a is connected to an upper
portion of each middle polishing solution distribution apparatus
10b. Here, although two strips of the branch piping 20a are
illustrated in FIG. 5, it is also possible to arrange three or more
strips thereof.
[0045] One end of each branch piping 20b is connected to a lower
portion of the middle polishing solution distribution apparatus
10b. Each branch piping 20b passes through a through hole (not
illustrated) arranged at a hanging plate 33 for hanging the upper
platen 31 and the other end thereof is connected to the upper
platen 31.
[0046] In the present embodiment, the polishing solution
distributed in the circumferential direction of the platen 30 by
the upper polishing solution distribution apparatus 10a is further
distributed by the plural middle polishing solution distribution
apparatuses 10b to be distributed and supplied to each portion of a
donut-shaped area sandwiched by the upper platen 31 and the lower
platen 32.
[0047] In the present embodiment being similar to the first
embodiment, the branch bodies of the polishing solution
distribution apparatuses 10a, 10b can be consistently maintained in
the leveled posture against the dropping direction of the polishing
solution without being affected by inclination of the installation
location of the polishing solution distribution apparatuses 10a,
10b as being supported by the universal joint mechanism.
Accordingly, the polishing solution can be evenly supplied to the
area sandwiched by the upper platen 31 and the lower platen 32.
[0048] FIG. 6 illustrates a modified example of the branch piping
20. As illustrated in FIG. 6, in the case that there is a fear of
disturbing movement of the branch body 12 as a result of the large
number of the branch piping 20, it is also possible to connect the
branch piping 20c shorter than the branch piping 20 of the first
embodiment to the delivery port 123 of the branch body 12 and to
arrange a funnel 60 as directing an upper end opening portion 61 to
the upper side below the branch piping 20c. Then, a lower end hole
62 of the funnel 60 is connected to piping 70 which is arranged
fixedly and the polishing solution is only required to be supplied
to a predetermined position of the platen 30 side from the piping
70. With this configuration, movement of the branch body 12 is not
disturbed by the branch piping 20c. In addition, when the funnel 60
being sufficiently large compared to a movement range of the branch
body 12 is arranged, solution leakage from the branch piping 20c
can be prevented.
[0049] Here, it is also possible to arrange the upper end opening
portion 61 of the funnel 60 below the delivery port 123 of the flow
passage 121 and to supply the polishing solution directly to the
funnel 60 from the delivery port 123 without connecting the branch
piping 20c to the delivery port 123.
[0050] The polishing solution distribution apparatus according to
the present invention is preferably adopted to a three-way
polishing apparatus (including a lapping apparatus) which is
constituted with three motional elements being rotating of the
lower platen 32, spinning of the carrier 37 and revolving of the
carrier 37.
[0051] In a four-way polishing apparatus with rotation of the upper
platen 31 in addition to the above three motional elements, the
polishing solution supplied to the area sandwiched by the upper
platen 31 and the lower platen 32 is averaged to some extent by the
rotation of the upper platen 31. However, when the rotation of the
upper platen 31 is slow or the size of the platen 30 is large,
deviation of the distribution quantity is hardly averaged.
Therefore, in such a case, it is effective to utilize the polishing
solution distribution apparatus for a four-way polishing
apparatus.
[0052] Improvement of deviation of polishing solution supplying
with the polishing solution distribution apparatus is effective
especially for a large workpiece and a large platen. For example,
it is effective for an apparatus of which workpiece maximum
dimension is equal to or larger than 400 mm or of which platen
outer diameter is equal to or larger than 1700 mm.
* * * * *